April 19, 1851

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Features

Gregory's Engine Power-Regulator

To Dye Hair Black Instantaneously

Railroad Law in Ohio

German Railroads

How We Pay for Tea

Reflection of Light and Sound

Metallic Life Boats

Foreign Correspondence

Mineral Naptha

Expense not Spared

Compact Mortising Machine

A Golden Model

Professor Jacobi

Steam Job Printing

The Three Cent Coins

California Fifty Dollar Gold Piece

Improvement in Forge Fires

Steamboat Challenge

List of Patent Claims

Gas Light

Patent Cases

Earthenware Pipes and Machinery

A Curious Rudder—Necessity the Mother of Invention

New Edition of the Patent Laws

To Remove Paint from Clothes

Mechanics

George Hudson the Railway King

Hydraulics

Scientific Memoranda

Departments

From the Editor

To Correspondents

Letters

Paragraph to Editors and Publishers

Purchase To Read More

Digital Issue ?Read or download this issue’s articles online. *A printed copy of this issue is not included. $7.99

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